content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2011, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
   * Other names may be trademarks of their respective owners.]
   *
   * ----------------------
   * IntervalXYDataset.java
   * ----------------------
   * (C) Copyright 2001-2009, by Object Refinery Limited and Contributors.
   *
   * Original Author:  Mark Watson (www.markwatson.com);
   * Contributor(s):   David Gilbert (for Object Refinery Limited);
   *
   * Changes
   * -------
   * 18-Oct-2001 : Version 1, thanks to Mark Watson (DG);
   * 22-Oct-2001 : Renamed DataSource.java --> Dataset.java etc (DG);
   * 06-May-2004 : Added methods that return double primitives (DG);
   * 15-Sep-2009 : Added clarifications to API docs (DG);
   *
   */
  
  package org.jfree.data.xy;
  
  /**
   * An extension of the {@link XYDataset} interface that allows an x-interval
   * and a y-interval to be defined.  Note that the x and y values defined
   * by the parent interface are NOT required to fall within these intervals.
   * This interface is used to support (among other things) bar plots against
   * numerical axes.
   */
  public interface IntervalXYDataset extends XYDataset {
  
      /**
       * Returns the lower bound of the x-interval for the specified series and
       * item.  If this lower bound is specified, it should be less than or
       * equal to the upper bound of the interval (if one is specified).
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The lower bound of the x-interval (<code>null</code> permitted).
       */
      public Number getStartX(int series, int item);
  
      /**
       * Returns the lower bound of the x-interval (as a double primitive) for
       * the specified series and item.
       *
       * @param series  the series (zero-based index).
       * @param item  the item (zero-based index).
       *
       * @return The lower bound of the x-interval.
       *
       * @see #getStartX(int, int)
       */
      public double getStartXValue(int series, int item);
  
      /**
       * Returns the upper bound of the x-interval for the specified series and
       * item.  If this upper bound is specified, it should be greater than or
       * equal to the lower bound of the interval (if one is specified).
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The upper bound of the x-interval (<code>null</code> permitted).
       */
      public Number getEndX(int series, int item);
  
      /**
       * Returns the upper bound of the x-interval (as a double primitive) for
       * the specified series and item.
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The upper bound of the x-interval.
       *
       * @see #getEndX(int, int)
       */
      public double getEndXValue(int series, int item);
  
      /**
       * Returns the lower bound of the y-interval for the specified series and
       * item.  If this lower bound is specified, it should be less than or
       * equal to the upper bound of the interval (if one is specified).
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The lower bound of the y-interval (<code>null</code> permitted).
       */
      public Number getStartY(int series, int item);
  
      /**
       * Returns the lower bound of the y-interval (as a double primitive) for
       * the specified series and item.
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The lower bound of the y-interval.
       *
       * @see #getStartY(int, int)
       */
      public double getStartYValue(int series, int item);
  
      /**
       * Returns the upper bound of the y-interval for the specified series and
       * item.  If this upper bound is specified, it should be greater than or
       * equal to the lower bound of the interval (if one is specified).
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The upper bound of the y-interval (<code>null</code> permitted).
       */
      public Number getEndY(int series, int item);
  
      /**
       * Returns the upper bound of the y-interval (as a double primitive) for
       * the specified series and item.
       *
       * @param series  the series index (zero-based).
       * @param item  the item index (zero-based).
       *
       * @return The upper bound of the y-interval.
       *
       * @see #getEndY(int, int)
       */
      public double getEndYValue(int series, int item);
  
  }
  